Pressure applying and relieving device



Aug. 21, 1951 F. T. N. PATTEN PRESSURE APPLYING AND RELIEVING DEVICE Filed Feb. 17, 1950 "WI/Aw Francis Z'A Paffen INVENTOR.

Patented Aug. 21 1951 UNITED STATES PATENT QFFICE PRESSURE APPLYING AND RELIEVING [DEVICE 2 Claims.

This invention relates to new and useful improvements in pressure applying and relieving devices.

One object of the invention is to provide an improved pressure applying and relieving device having a passageway connecting its inlet and outlet and an exhaust adapted to communicate with the outlet for relieving the applied pressure when the inlet pressure is reduced.

Another object of the invention is to provide an improved device, of the character described, having pressure-responsive means for controlling the communication of the exhaust with the outlet and exposed to the inlet pressure so as to open said exhaust and relieve the pressure applied through said outlet when said inlet pressure falls below a predetermined point.

A further object of the invention is to provide an improved device, of the character described, wherein the pressure-responsive means is exposed to the inlet and applied pressures so as to be operable by the diiierential there-between, valve means being provided for shutting off communication between the inlet and outlet when the applied pressure equals or exceeds the inlet pressure so as to trap said applied pressure for actuating said pressure-responsive means upon reduction of said inlet pressure.

Still another object of the invention is to provide an improved device, of the character described, wherein the passageway is in constant communication with the exhaust through bleed means so as to permit reduction of the inlet pres sure upon closing of the valve means.

A construction designed to carry out the invention will be hereinafter described together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawing, wherein an example of the invention is shown, and wherein:

Fig. 1 is a perspective view of a pressure applying and relieving device constructed in accordance with the invention,

Fig. 2 is an enlarged, transverse, vertical, sectional view of the device, showing the application of pressure,

Fig. 3 is a View, similar to Fig. 2, showing the relieving of the applied pressure, and

Fig. 4'is a horizontal, cross-sectional view, taken substantially on the line 44 of Fig. 2.

In the drawing, the numeral l designates a device for applying air or other fluid under pressure to a cylinder (not shown) or other member to operate or test the same and then relieve the pressure fluid by exhausting the same. The device includes a body ll having an inlet port l2 adjacent its upper end, an outlet port H3 at its lower end an exhaust port it substantially opposite its inlet port. If desired, an auxiliary inlet port l5 ma be provided in the upper end of the body adjacent and at substantially a right angle to the inlet port E2 to facilitate installation of the device. When not in use, the auxiliary inlet I5 is closed by a suitable screw-threaded plug l 5. For applying fluid under pressure to the device, a pipe I? is screw-threaded in the inlet port [2 and has a valve l8 connected therein. Although shown as being manually operable, the valve l8 may be of any suitable or desired type.

An angular passageway l9, having an upright leg or portion 26 and a lateral leg or portion 2!, extends between the inlet port and the outlet port l3 with its upright leg communicating with the ports [2 and I5 and its lateral leg communicating with said outlet port. The latter has a pipe or other conduit 22 screw-threaded therein for conducting the pressure fluid to the member which is not illustrated. The lateral leg 25 of the passageway it extends beyond the outlet port and is enlarged at its juncture with said port to provide a counterbore 23 for receiving a spring-pressed valve member 2t. An annular valve seat 25 is formed in the passageway adjacent the outlet port by the provision of the counter-bore 23 and is adapted to be engaged by a circular valve element or head 25 carried by the valve member 2 for shutting off communication between said passagewa and said outlet port.-

The head 26 is connected to the valve member by a reduced neck or stem 21 and is held in engagement with the seat 25 by a coiled spring 28 which is confln'ed by a flanged follower 29 screw-thread'- ed in the outer end of the counterb-ore 23 (Fig. 4). Due to the provision of the follower 25, the compression of the spring 28 may be adjusted to vary the pressure required to open the valve member.

Fluid under pressure is admitted to the passageway [9 by opening of the valve 18 and when the pressure of this fluid is sufficient to overcome the force of the spring 28, the valve head moves away from its seat so as to permit said fluid to flow through the outlet port into the pipe 22. When this applied pressure equals or exceeds the pressure in the passageway, the valve member closes to shut off further flow. This equalization of pressure may be brought about by closing of the control valve l8. Upon closing of the valve member the pressure applied through the outlet port and its pipe is trapped.

For relieving the trapped pressure fluid, an upright duct 30 communicates with the outlet port and is preferably in axial alinement therewith so as to form a continuation thereof and extend substantially parallel to the upright leg 20 of the angular passageway. The lower end of the duct 33 opens into the counterbore 23 beyond the valve head and its seat is established due to the reduced neck 21 of the valve member 24. An enlarged circular chamber 3| is disposed above and in communication with the duct 30, preferably being axially alined therewith. An angular duct 32 extends inwardly and upwardly from the exhaust port l4 and has its inner end communicating with the lower end of the chamber 3| adjacent the upper end of the duct 33. Communication between the chamber and the ducts 33 and 32 is controlled by a pressure-re sponsive means in the form of a circular valve disk or element 33 of rubber or other suitable elastic or flexible material. The disk 33 is of a diameter sufficient to overlie the ends of the ducts and normally engages a complementary seat 34 formed in the lower end of the chamber. A flanged gland or cap 34 is screw-threaded in the upper end of the chamber to close the top thereof and loosely confine the disk. Suitable notches 35 are cut in the lower peripheral edge of the cap flange to prevent the disk from clinging to said flange when raised from its seat 34. The chamber is in constant communication with the upright leg 20 of the angular passageway by means of a lateral duct 36. Thus, the upper surface of the disk is exposed to the pressure of the fluid in the passageway and said disk is held in engagement with its seat by said pressure since only a small portion of its underside is exposed to the pressure of the fluid in the duct 30.

The angular passageway is in constant communication with the exhaust port by means of an angular bleed port 3!- which extends from the upright leg 20 to the bottom of the chamber and an annular groove 38 formed in said chamber bottom in concentric relation to the duct 38 so as to communicate with the angular duct 32. An adjustable needle valve 39, having a lock nut 40', is screw-threaded in a port 4| so as to extend across the passageway leg 23 for coacting with the lower end of the angular bleed port 3?. By adjusting the needle valve 39, the desired venting or bleeding of fluidfrom the passageway is obtained due to the constant communication between said passageway and the exhaust port. It is noted that the disk 33 does not shut off this communication.

As has been explained, the valve member 24 closes whenever the applied pressure equals or exceeds the pressure in the passageway. This applied pressure fluid is trapped due to the pressure-responsive means or disk being held in engagement with its seat 34 by the pressure of the fluid within the passageway. Due to the port 36, the chamber 3! is in constant communication with the passageway and the pressures therein are the same. In order to relieve the trapped pressure fluid, it is necessary to shut off the inlet pressure and this may be accomplished by closing the valve I8. Upon closing of this valve, the pressure within the passageway and chamber is reduced by bleeding through the angular port 31, groove 38 and angular duct 32 to the exhaust port [4. A sufficient reduction of the inlet pressure causes the pressure of the trapped fluid to lift the disk from its seat, whereby said fluid escapes through the duct 32 to the outlet port.

Since the lower surface of the lifted disk is above the lower margin of the port 36, the pressure fluid in the passageway also is exhausted. If desired, a pipe or other conduit 42 may be screw-threaded into the exhaust port for carrying off the pressure fluid. When pressure fluid is again admitted to the passageway by opening the valve IS, the disk is re-engaged with its seat to close off the duct 30 from communication with the duct 32. If the disk remains off of its seat after the previous exhausting of the pressure fluid, the pressure of the incoming fluid flowing beneath said disk and acting upon its upper surface seats the same. Thus, seating of the disk is not dependent upon gravity and the pressure fluid is again applied when it builds up sufliciently to open the valve member 24.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

1. A pressure applying and relieving device including, a body having a passageway, the passageway having an inlet and an outlet for receiving and discharging fluid under pressure, valve means between the outlet and passageway for closing said passageway when the outlet pressure equals the inlet pressure so as to trap said outlet pressure, an exhaust adapted to communicate with said outlet, pressure-responsive means exposed to the inlet and outlet pressures for controlling communication between the exhaust and outlet whereby said communication is established when the inlet pressure falls below a predetermined point, and bleed means extending between said passageway and exhaust for permitting escape and reduction of the inlet pressure.

2. A pressure applying and relieving device including, a body having an inlet, an outlet and an exhaust, a passageway in the body for conducting fluid under pressure from the inlet to the outlet, valve means in the passageway for shutting off said outlet from said passageway when the outlet pressure equals the inlet pressure so as to trap said outlet pressure, a chamber in the body communicating with the exhaust, inlet and outlet, a valve member in the chamber exposed to the inlet and outlet pressures for closing off said exhaust and outlet, the valve member being held closed by said inlet pressure and being opened by said outlet pressure when said inlet pressure is reduced, and vent means communicating with said passageway for reducing the inlet pressure.

FRANCIS T. N. PATTEN.

REFERENCES CITED UNITED STATES PATENTS Name Date Messiter Aug. 5, 1902 Number 

